10 Best Portable Greenhouse Heaters 2026 in the United States

The BioGreen Electric Greenhouse Heater & Fan (PALMA) is a solid choice for small to medium greenhouses up to about 120 square feet. It offers flexible heating power with two settings (750W and 1500W), giving you control over energy use and warmth. Its digital thermostat is a handy feature that automatically maintains your chosen temperature between 32°F and 185°F, making it easy to keep plants comfy without constant adjustment. The built-in fan mode helps circulate air evenly, preventing hot spots and protecting plants from overheating.

It’s splash-proof (IPX4), so it can handle humid greenhouse conditions or occasional water splashes without worry. With a compact, portable design and a tabletop mount, you can easily move it around where needed. It runs on standard 120V electric power, which is common and convenient but means you need access to an outlet. While it’s energy efficient for its size and includes overheat protection for safety, its coverage suits smaller spaces best—larger greenhouses will need multiple units or a more powerful heater.

This dependable and user-friendly heater is ideal if you want precise temperature control in a compact electric heater designed specifically for greenhouse use.

The Dr Infrared Heater DR-268 is a solid choice for those seeking a portable greenhouse heater. With its heating capacity of up to 1500W, it effectively warms areas of 150-200 square feet, making it suitable for greenhouses, garages, and sheds. One of its standout features is the built-in digital thermostat, which allows for precise temperature control, ensuring that your plants stay at the right temperature without wasting energy. User-friendly features like the digital display and selectable Auto or Manual modes also make operation straightforward, even for those who aren't tech-savvy.

Safety is a priority with this heater, as it includes features like overheat protection and is designed to be water-resistant (rated IPX5), allowing it to be used both indoors and outdoors without worrying about damage from moisture. Its construction from dual layers of aluminum helps retain heat effectively, making it especially useful in colder environments.

There are some considerations to keep in mind. The heater requires assembly and, while it has multiple mounting options, it may not be as easy to reposition once installed. Additionally, while it’s energy efficient, being electric means it will add to your electricity bill, especially with continuous use. Lastly, with a one-year limited warranty and USA-based customer support, users can feel secure about their purchase. This heater is particularly suited for gardeners and growers looking for a reliable, versatile heating solution that can easily adapt to different spaces and conditions.

The Mr. Heater MH9BX-Massachusetts/Canada approved portable propane heater is designed to provide reliable warmth for spaces up to 225 square feet. With its heating capacity ranging from 4,000 to 9,000 BTU, this heater is suitable for smaller greenhouses, especially during cold seasons. One of its notable strengths is nearly 100-percent efficiency, ensuring most of the energy from the propane is converted to heat. However, users should be aware that its performance may decline at altitudes above 7,000 feet, as it may shut off unexpectedly.

Safety is a prominent feature of this heater, with an auto shut-off mechanism if tipped over, if the pilot light goes out, or if low oxygen levels are detected, which is crucial for peace of mind and preventing accidents. The heater is also portable, weighing just 9.5 pounds, with a fold-down handle for easy transportation, making it ideal for moving around different sections of a greenhouse or even using in other outdoor settings.

The heater connects to a propane tank, which is not included, and has a runtime of about 5.6 hours at its lowest BTU setting. While running on propane, it should be noted that using unauthorized accessories can void the warranty and potentially cause safety hazards. It’s important to ensure proper ventilation when used indoors, despite its outdoor usage approval, to prevent any safety risks. Though the heater receives high ratings from users, indicating satisfaction with its performance and reliability, it's crucial that the heater is assembled correctly, following the instructions in the included manual. It's an efficient choice for greenhouse enthusiasts looking for portable heating solutions, though one should weigh the costs of propane usage and ensure it suits their specific environmental needs.